Excavating tooth



June 13, 1961 A. v. STRATTON EXCAVATING TOOTH 3 Sheets-Sheet 1 FiledAug. 5. 1957 INVENTOR ARV/N L/ STRATTON ATTORNEYS June 13, 1961 A, v,STRATTON 2,987,838

EXCAVATING TOOTH Filed Aug. 5, 1957 3 Sheets-Sheet 2 5 INVENTOR ARV/N lSTRATTON A. V. STRATTON EXCAVATING TOOTH June 13, 1961 3 Sheets-Sheet 5Filed Aug. 5. 1957 INVENT OR BY ARV/N V STRATTON A T TOPNEVS United Stats P te 2,987,838 EXCAVATING TOOTH Arvin V. Stratton, 181 E. 200 South,Cedar City, Utah, assignor of one-third to Elton Stratton Filed Aug. 5,1957, Ser. No. 676,218 Claims. (Cl. 37142) This invention relates to anexcavating tooth of the type that includes an adapter and a replaceabletooth point therefor, and which tooth is one of a plurality of thecorresponding teeth used on a power-driven shovel dipper and the like.

One of the objects of the invention is the provision of a tooth of theabove character having a substantially longer life than the usual toothheretofore used, and which tooth includes a point that is quickly andeasily replaceable.

A still further object of the invention is the provision of an improvedtooth point that is formed to cooperate with the adapter in a mannerthat will reduce the wear on the adapter.

In explanation of the above, the teeth on power-driven shovel dippersusually wear away in several places faster than others. The tooth point,being the portion that has the digging edge, naturally tends to wearaway faster than the remainder. The adapter is the portion of the tooththat is connected with the bucket or dipper, and it also receivesconsiderably more wear where the material dug by the point moves over itinto the bucket.

Replaceable tooth points are old in the industry and they are normallyconnected with the adapter by means of a pin of some kind. The adapterusually has a nose that extends into a socket in the tooth point, andthe pin usually extends through the upper and lower sides of the socketand through said nose. However, in the normal use of'the dipper orbucket that employs conventional teeth of the above character, thepoints andadapter frequently break where the key secures them together.Also the adapters wear out almost as rapidly as the points.

With the present structure no breakage occurs and the adapters will lastalmost indefinitely, or are so constructed as to enable them to readilybe maintained so that-they will last almost indefinitely.

Other objects and advantages will appear in the description and in thedrawings.

In the drawings,

FIG. 1 is an isometric view showing the adapter and a tooth point inwhich the latter is slightly separated from the adapter to showstructure. The key for holding the point on the adapter is not shown inthis view.

FIG. 2 is a fragmentary isometric view of the nose on the adapter thatis adapted to extend into a tooth point.

FIG. 3 is a top plan view of an assembled tooth.

FIG. 4 is a cross sectional view taken along line 4--4 of FIG. 3.

FIG. 4a is a fragmentary sectional view showing a slight modification ofthe structure of FIG. 4.

FIG. 5 is a bottom plan view of the tooth of FIG. 3.

FIG. 6 is a part sectional and part elevational view of a tooth that isa modification of the one'shown in FIGS. 1 to 5.

FIG. 7 is a sectional view showing a modification of the tooth of FIG.6.

FIG. 8 is a fragmentary top elevational view of a slight modification ofthe adapter shown in FIG. 1.

FIG. 9 is a fragmentary top elevational view showing a still furthermodification of the adapter of FIG. 1.

FIG. 10 is a view similar to that of FIG. 1 but showing a modificationof the structure of FIG. 1 in which a replaceable wear plate is used ata critical point of wear.

FIG. 11 is a sectional view taken along line 11-11 of FIG. 10 but withthe two parts of FIG. 1 in assembled relation instead of being spacedapart.

FIG. 12 is a perspective view looking upwardly at the. underside of awear plate that is slightly modified from the plate shown in position onFIG. 10.

FIG.13 is a view similar to that of FIG. 11, but showing a reversal ofthe structure of FIG. 11 insofar as the dove-tail connections areconcerned.

In the description the words forward and forward1y"; rear and rearwardlyare used with reference to the digging edge of the tooth point which isat the forward end of the tooth, and with reference to the tang that ison the adapter for securing the tooth to the dipper or bucket, such tangbeing at the rear end of the tooth.

In detail, referring to FIG. 1 the adapter comprises a shank portiongenerally designated 1, and a tooth point, generally designated 2. Theshank portion 1 may be of any suitable type insofar as its structure forsecuring it to a bucket or dipper is concerned. Normally the shankportion will include rearwardly opening recesses 3 in its oppositelateral sides and a rearwardly projecting tang 4 that is used forsecuring the shank portion to a dipper or bucket.

The upper and lower surfaces of the shank portion, forwardly of the tang4, extend convergently in a direction forwardly from the tang.

A wedge shaped nose 5 is integral with the shank portion 1 and projectsforwardly therefrom. Said nose has upper and lower wedge faces thatextend convergently in a forward direction from the shank portion. Thevertical opposite sides of said nose are substantially parallel;

Said side surfaces and said upper and lower wedge faces of the said nose5 are spaced inwardly from the side and top and bottom surfaces of theshank portion '1, thereby providing forwardly facing upper and lowershoulders 6, 7 above and below nose 5, and forwardly facing shoulders 8at the sides of the nose. These forwardly facing surfaces are preferablycoplanar.

The upper surface of the shank portion 1 that is adjacent to shoulder 6is preferably formed with spaced grooves forming ribs 9 (FIG. 2) betweenadjacent grooves,

' and which grooves and ribs are parallel with shoulder 6.

The forward rib 9 is preferably spaced slightly rearwardly of shoulder6, and also the ends of the ribs are preferably spaced slightly from thelateral sides of the shank portion. The grooves between the ribs 9 arefilled with a filler 10 of extra hard metal integrally united with themetal of the shank portion, which hard filler may be that of a hardwelding rod applied by a welding operation. This filler also extendsalong the sides of the adapter across the ends of ribs 9, and along theforwardly facing side of the front or forward rib. The face of shoulder6 and the forward side of the filler along said forward rib may besubstantially even.

While the forward ribs 9 shown in FIGS. 1, 2 are shorter than theothers, the ribs may all be of the same length, as seen in FIG. 9 at 11.Also, the ribs, as seen at 12 in FIG. 8, may be relatively short and atright angles to the shoulder on the shank portion. In any event, thefiller of hard metal will extend along shoulder 6, or the correspondingshoulder in FIGS. 8, 9, and along the sides of the shank portion at theends of the ribs (FIGS. 1, 9) or along the end ribs as seen in FIG. 8.The tooth point 2 is formed with a rearwardly opening socket in whichthe upper and lower sides of which rearwardly facing edge extendingapproximately from one side of the tooth point to the other along therear edge of the upper wall 15. This upper wall is preferably relativelythick, as seen in FIG. 4, and the tongue 18 is formed on the lower halfof the wall 15.

The central portion of tongue 18 is thickened to provide a substantiallyrectangular central section 19 that is flush on its upper surface withthe upper surface of the wall 15. This section is integral with thetongue 18 and with wall 15 and projects rearwardly from wall 15 thewidth of the tongue. The opposite lateral sides 20 of the section 19 arepreferably approximately vertical.

The shank portion 1 is formed with a recess 21 that opens forwardly ofsaid portion through the forwardly facing shoulder 6 at a point justabove nose 5. This recess is complementary to the tongue 18 and section19. The lower wall 16 of the tooth point 2 is formed with a rearwardlyprojecting portion 22 centrally between its ends. This portion 22extends horizontally a substantial distance along the rear edge of wall16 and is disposed in a plane that is substantially parallel with theplane in which the tongue 18 is disposed. It is spaced upwardly from thelower surface of wall 16 thereby providing a rearwardly facing shoulderalong its juncture with wall 16.

The shank portion 1 is formed with a recess 23 that opens forwardlythrough the forwardly facing shoulder 7 on said shank portion just belowthe nose 5. This recess '23 is complementary to the projection 22. IWhen the tooth point is fitted on the nose 5 the upper surface of wall15 is spaced below the upper surface of the shank portion for the majorportion of its width. This spacing may substantially equal the verticalthickness of the exposed forwardly facing .filler 10 that is along theforward side of the rib 9 that is nearest to nose 5 and to the wall 15.Thus the entire exposed forwardly facing shoulder 6 may be of extra hardmetal that is harder than the remainder of the metal of the shankother-than that of filler 10.

'In the form of the invention shown in FIGS. 1, 2 a pair of parallel,upstanding ribs 24 are in upward continuation of the side walls of thetooth point. These extend from the rear edges of the lateral sides ofsaid point to approximately the forward edge 17 of the tooth, and theyare of progressively reduced thickness in a direction from said rearedges toward said digging edge, with the rear edges being of a heightabout equal .to the height of shoulder 6.

The tooth point 2 is releasably secured onto nose 5 by means of anelongated, vertically extending key 25 that extends through alignedopenings in walls 15, 16 and in nose 5.

These key receiving openings, designated 26 for the opening in wall 15,and 27 for the opening in nose 5, and 28 for the opening in wall 16 arepositioned midway between the opposite lateral sides of the tooth pointand nose 5.

Key 25 has tapered forward and rear edges making it thicker at its upperend than at the lower end and the upper end of said key is provided witha forward extension 29 integral therewith. This extension is adapted tobe received in an enlargement 30 of theopening 26 at the forward side ofsaid opening.

The lower end of the key projects below wall 16 and is formed with anopening in which is held a transversely extending pin 31. The ends ofthe pin 31 project to opposite sides of the lower end of key 25, andsaid pin extends parallel with the digging edge 17. The projecting endsof said pin fit in complementarily formed recesses 32 that are in thelower face of wall 16. Said lower wall 16, in turn, is formed with adownwardly projecting guard lip 33 that extends across the forwardlyfacing :edge of the projecting lower end of key 25.

The forward extension 29 on the upper end of key 25 overliesahelicalspring=34, whichspring, in turn,-is seated at its lower end in ashallow upwardly opening recess formed in nose 5 at the forward edge ofkey 25. This spring is normally under expanding tension to yieldablyhold the pin 31 in recesses 32, and when the pin is so held, the uppersurface of the key 25 may be substantially flush with the upper surfaceof wall 15, or even slightly below said surface.

In order to remove the tooth point, it is merely necessary to force key25 downwardly until pin 31 can be knocked out of the opening in the key.The new tip is locked onto the nose by forcing key 25 downwardly againstthe resistance of spring 34 until the pin 31 can be inserted into theopening in the lower end of the key, and after the pin is so insertedand the key is released, the pin will be held in recesses 32.

In operation, the earth, sand or other material that is being dug, willpass over the upper surfaces of the tooth point and adapter and into thedipper. A portion of the earth, sand, etc. is caught against theshoulder 10 to form a layer over which the remainder of the materialpasses, hence the Wear on the adapter is materially less than where theupper surface of the adapter and tooth point are flush with each other.The ribs 24 assist in holding the dirt on the tooth point ahead ofshoulder 6, and they also strengthen the tooth point, making it possibleto use a lighter weight point that will not bend under the liftingstrains. Whether or not the ribs 24 are used, the principle is generallythe same and the dirt held on the tooth point ahead of the shoulder 6will result in greatly reduced wear on the tooth point as well as theforward upper surface end of the shank portion.

With respect to the foregoing, it may be noted that the tempering of themetal along the digging edge or the use of a hard metal facing alongsaid edge, has been done, but the sliding of the dirt past said edge andover the upper surfaces of the tooth point and the adapter wears awaythe metal rearwardly of said digging edge and the tooth points havequite frequently broken oh along the key openings. By providing theshoulder 6 of hardened metal so that the layer of dirt ahead of theshoulder will support the dirt that slides over said layer, this wear onthe tooth does not occur.

Various efforts have heretofore been made to prevent the breakage of theadapter point and to prevent loose play of the tooth point on theadapter. Usually these efforts have taken the form of extensions, earsor reinforcements on the tooth point that are exposed to wear, and oncethis wear reaches a certain amount, the breakage will occur.

In the present instance, the tongue 18 and projection 22 fit into theshank portion 1 or adapter to give adequate strength where most of thestrain occurs, and as these portions are within the body of the adapterthey cannot be worn off or weakened. Also the section 19 providesadditional strength and eliminates loose play between the tooth pointand the adapter.

The structure of the key is important in that heretofore most attemptsto hold the key in the openings has involved forming the key with arecess or depression in which a rubber block or other element isyieldably urged. In actual practice these attempts have beenobjectionable for the reason that the rubber block or metal urged intothe key depression has frequently broken off and has so wedged the keyas to make it impossible to remove it without resorting to a cuttingtorch.

In the present instance, the sides of the key are straight, hence it caneasily be driven out of the openings in which it is fitted.

FIG. 4a shows the same structure as is shown in FIG. 4 except that arubber block 35 replaces spring 34.

In the form of invention shown in FIGS. 6, 7, the same adapter or'shankportion 1 is shown, as in FIGS. 1 to 5, hence the same numbers will beused in referring to it.

The tooth point is much the :same as the one shown in FIGS; 1 to 5, withthe main difference being inthe-manper in which the tooth point issecured to the adapter.

In FIG. 6 the tooth point, generally designated 36, is formed with arearwardly opening socket for the nose 5 of the adapter. Upper wall 37and lower wall 38 form the upper and lower sides of the socket, andaligned openings 39, 40, 41 respectively formed in the upper wall 37,nose 5 and lower wall 38 are to receive a vertically extending taperedkey 42.

This key 42 does not have any lateral extension on its upper end, butthe sides of the key extend straight to the upper end. However, thelower and thinner end of the key is formed with a slight rearwardprojection 43 that is adapted to hook over the rear edge of the opening41 when the lower end of the key is urged rearwardly. Openings 48, 41are sufiiciently wide in the front to rear direction to enable the lowerend of key 42 to swing forwardly a sufiicient amount so that projection43 will clear the rear edge of the opening 41 to permit the key to bedriven out of the openings 40, 41, 39 in an upward direction, as seen inFIG. 6.

The lower end of the opening 40 at the forward side of the key is formedwith a recess in which a rubber plug or body 44 is held, and it is theexpansion of this plug against the forward side of the lower end of thekey that urges the projection 43 into holding relation with the rearedge of opening 41.

In this instance the projection 43 on the key is what holds the key inthe openings that are in the tooth point and in the adapter and therubber block 44 merely prevents the projection from moving out ofengagement with the lower wall of the point, but it does not, in itself,hold the key against withdrawal from the tooth.

It should be noted that there is virtually no wear on the bottom of thetooth point during digging operations.

The modification shown in FIG. 7 is the same structure as is shown inFIG. 6 except that a spring 45 is used instead of the rubber block orbody 44 and a wear button is interposed between the spring and the keyto slidably engage the latter. In FIGS. 6, 7 it is seen that the upperend of the key 42 has a slight forward projection 47 to act as a limitstop, although the taper of the pin would accomplish the same purpose ifthe portion of the pin in the opening in wall 37 were accurately fitted.

In FIGS. 4 and 6 the rear portion 48 (FIG. 4) and 49 (FIG. 6) of thelower surface of the nose extends substantially parallel with the upperwedge surface of said nose which enables the rearward projection 22(FIG. 4) and 59 (FIG. 6) to be formed in a manner to enter thecomplementarily formed recess in the shank portion.

In FIG. 10, a hard, replaceable metal plate 51 is used instead of thematerial 10. The upper surface of the shank portion 52 is cut away toreceive this plate, and dovetail ribs 53 formed on the lower side ofsaid plate extending longitudinally of the tooth are adapted to slideendwise into complementarily formed dovetail groove 54 (FIG. 11) formedin the relieved upper surface of the shank that is adapted to receiveplate 51 (FIG.

The tooth point on the adapter has the rearward tongue 56 and thecentral section 57 the same as tooth point 2 of FIG. 1, and the lowerside of plate 51 may be recessed at 58 to receive said section 57.

In the form shown in FIG. 10, the opposite sides of the nose 55 may alsobe formed with dovetail grooves 59 that are parallel with the upper wall69 of the point 61, and the opposite side walls 62 of the point areformed with inwardly projecting ribs 63 that are complementary to thegrooves 59 so that said ribs will slide endwise into the grooves 59 uponpositioning the point 61 on nose 55. The ribs 63 preferably projectrearwardly of the rear end of the tooth, as at 64 (FIG. 10) so as toenter complementarily formed recesses 65 in the shank at the sides ofthe rear end of nose 55.

' The lower forward portion 67 of the shank 52 projects forwardly and isintegral with nose 55 and extends into the complementarily formedrearwardly and downwardly directed recess 68 formed in the lower portionof the tooth 61 (FIG. 10).

The key opening 69 extends through the upper wall of the point andthrough the nose and portion 61 and the same key structure is used as inFIG. 4 except that the lower wall of the point 61 terminates ahead ofthe key, and the key locking pin 31 lies in a recess in the lower sideof the portion 67.

In FIG. 12, the plate 76 shown therein has transverse ribs 71 ofdovetail contour to fit in transverse complementarily formed grooves(not shown) in the adapter. This and a recess 72 in the lower side ofthe plate would receive the section 57 to lock the plate againstmovement transversely of the adapter or shank.

In FIG. 13 the same general structure is used as in FIG. 11 except thatthe dovetail ribs and grooves indicated in FIG. 11 are reversed, andinstead of the ribs 53 being in the plate 51 of FIG. 11, the ribs 73 areon the adapter and the recesses 74 therefor are on plate 75. Also, inFIG. 13 instead of the ribs 63 being on the side walls of the toothpoint, as seen in FIG. 11, the ribs 76 are on nose 77 and recesses 78for said ribs 76 are in the side walls 79 of the point.

It is pertinent to note that the forward edge of plate 51 (FIG. 10) orplates or 75, provides the exposed shoulder against which dirt will beheld, the same as in FIG. 1. The upstanding portions 24 of the sidewalls is not shown in FIGS. 10 to 13 although it may be used if desired,particularly where sand or loose material is being loaded into thebucket or dipper. Also in FIG. 10 the tooth point covers the ends of thedovetail ribs and hence cooperates with the plate 51 to hold the latteron the adapter.

I claim:

1. An excavating tooth comprising, in combination, an adapter having ashank portion and an integral substantially Wedge-shaped nose havingopposite upper and lowerwedge faces, a separate tooth point formed witha rearwardly opening socket having an upper wall and a lower wallextending divergently relative to each other toward the open rear end ofsaid socket and defining the upper and lower sides of said open rearend, said upper and lower walls having generally opposed surfacesadapted to seat against said wedge faces, aligned openings formed insaid upper and lower walls and nose, a key within said openingsreleasably holding said tooth point on the nose of said adapter, saidtooth point having a digging edge at its forward end opposite to saidopen rear end of the socket therein, a shoulder on said adapter atsubstantially the juncture between said nose and said shank projectingabove the upper surface of said upper wall and facing generally towardsaid digging edge to cooperate with said upper surface for retaining alayer of earth along said shoulder over which earth dug by said tooth isadapted to pass, said adapter being formed with a recess formed in saidshank below said shoulder substantially equal to the width of said upperwall, a tongue integral with and projecting from said upper wall intosaid recess, said tongue including a central portion substantially equalto the thickness of said upper wall and having side portions at oppositesides of said central portion of less thickness than said centralportion and the contour of the inner surfaces of said recess beingcomplementary to the exterial contour of said tongue.

2. An excavating tooth comprising, in combination, an adapter having ashank portion and an integral substan tially wedge-shaped nose havingopposite upper and lower wedge faces, a separate tooth point formed witha rearwardly opening socket having an upper wall and a lower wallextending divergently relative to each other toward the open rear end ofsaid socket and defining the upper and lower sides of said open rearend, said upper and lower walls having generally opposed surfacesadapted to seat against said wedge faces, aligned openings formed insaid upper and lower walls and nose, a key within said openingsreleasably holding said tooth point on the nose of said adapter, saidtooth point having a digging edge at its forward end opposite to saidopen rear end of the socket therein, a shoulder on said adapter atsubstantially the juncture between said nose and said shank projectingabove the upper surface of said upper wall and facing generally towardsaid digging edge to cooperate with said upper surface for retaining alayer of earth along said shoulder over which earth dug by said tooth isadapted to pass, said shoulder being of harder material than thematerial of said shank and being secured on the latter, a recess formedin said shank below said shoulder opening forwardly toward said diggingedge and having an upper side, a lower side and rear side, said upperwall having a tongue integral therewith projecting into said recess,said tongue having a central portion substantially equal to thethickness of said upper wall and said central portion havingsubstantially vertical lateral sides, side portions on said tongue oflesser thickness than said central portion projecting laterallytherefrom and spaced below the upper surface of said central portion,said tongue terminating in a horizontally curved rear edge facing awayfrom said digging edge, and said upper, lower and rear sides of saidrecess being complementary in contour to the contour of said tongue.

3. An excavating tooth comprising, in combination, an adapterhaving ashank portion and an integral substantially wedge-shaped nose havingopposite upper and lower wedge faces, a separate tooth point formed witha rearwardly opening socket having an upper wall and a lower wallextending divergently relative to each other toward the open rear end ofsaid socket and defining the upper and lower sides of said open rearend, said upper and lower walls having generally opposed surfacesadapted to seat against said wedge faces, aligned openings formed insaid upper and lower walls and nose, a key Within said openingsreleasably holding said tooth point on the nose of said adapter, saidtooth point having a digging edge at its forward end opposite to saidopen rear end of the socket therein, a shoulder on said adapter atsubstantially the juncture between said nose and said shank projectingabove the upper surface of said upper Wall and perpendicular to saidupper surface and facing generally toward said digging edge to cooperatewith said upper surface for retaining a layer of earth along saidshoulder over which earth dug by said tooth is adapted to pass, upwardlyprojecting ridges integral with said upper wall extending from saidshoulder toward said digging edge, the rear edge of said upper wallbeing substantially in engagement with said shoulder, said shoulderbeing of substantially harder material than that of said shank, theupper surface of said shank and said ridges being sub stantiallycoplanar and the rear ends of said ridges being substantially inengagement with said shoulder, the face of said shoulder being flat andsubstantially at right angles to the upper surface of said tooth pointwhereby said shoulder and said tooth point will cooperate to retain suchlayer of dirt in a position protecting said shank against wear at saidshoulder.

4. An excavating tooth comprising, in combination, an adapter having ashank-portion and an integral substantially wedge-shaped nose havingopposite wedge faces; a separate tooth point formed with a rearwardlyopening socket having two walls extending divergently relative to eachother in a direction toward the open rear end of said socket providinggenerally opposed surfaces adapted to seat against said wedge faces,aligned openings respectively formed in said two walls and nose, a keywithin said openings removable therefrom for releasably holding saidtooth point on said nose, means on said key and on said tooth point inreleasable engagement with each other for holding said key stationarywithin said aligned openings, and yieldable means yieldably reactingbetween a-portion of said key and between a portion of said noseyie'ldalbly holding the means on said key and on said tooth point insaid engagement with each other, said two walls being positioned oneabove the other to provide an upper wall and a lower wall, said upperwall and said lower wall being integrally connected along their edgesthat are remote from the open rear end of said socket to form a diggingedge, said key being vertically elongated, the means on said key and themeans on said tooth point in said engagement with each other being,respectively, a lateral projection carried by said key at its lower endand part of the marginal portion around said opening in said lower wallinto which said key extends, the upper end of said key having a lateralextension projecting over a portion of-said nose, said yieldable meansbeing positioned between said-lateral extension and said nose.

5. An excavating tooth comprising, in combination, an adapter having ashank portion and an integral substantially wedge-shaped nose havingopposite wedge faces; a separate tooth point formed with a rearwardlyopening socket having two walls extending divergently relative to eachother in a direction toward the open rear end of said socketprovidinggenerally opposed surfaces adapted to seat against said wedgefaces, aligned openings respectively formed in said two walls and nose,a key within said openings removable therefrom for releasably holdingsaid tooth point on said nose, means on said key and on said tooth pointin releasable engagement with each other for holding said key stationarywithin said aligned openings, and yieldable means yieldably reactingbetween a portion of said key and between a portion of said noseyieldably holding the means on said key and on said tooth point in saidengagement with each other, said two walls being positioned one abovethe other to provide an upper wall and a lower wall, said upper wall andsaid lower wall being integrally connected along their edges that areremote from the open rear end of said socket to form a digging edge,said key being vertically elongated, the means on said key and the meanson said tooth point in said engagement with each other being,respectively, a lateral projection on said key at its lower end and partof the marginal portion around said opening in said lower wall intowhich said key extends, said key being tapered longitudinally thereofwith its upper end having the greatest width and in engagement withopposite edges of the opening formed in said upper wall; said lower endof said key being movable laterally in said last mentioned openingagainst the resistance of said yieldable means to free said lateralprojection from engagement with said part of said marginal portion, andsaid yieldable means being positioned between the lower end of said keyand said portion of said nose.

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